ér sūn zì yǒu ér sūn fú, mò wèi ér sūn zuò mǎ níu
儿 孙 自 有 儿 孙 福， 莫 为 儿 孙 做 马 牛

The children can take care of themselves when they grow up, so the parents do not have to work too hard for the future of their offspring.

解释 ( paraphrase )
子孙自有他们的福分，长辈不必操劳、担忧，为他们做牛做马。
这条谚语告诉我们：应该正确对待子孙后代的前途问题。子孙后代个人有自己的生活道路，家长过分地为他们忧虑，操劳是多余的。

This proverb tells us that the older generation should take a proper attitude toward the future of the younger generation. It is not necessary for parents to worry too much about their children, since they will make their own way in the world.

福：福分，享受幸福生活得命运。
Good luck, happiness.

造句 ( example )
儿孙自有儿孙福，莫为儿孙做马牛。抚养教育下一代，是父母的责任，但是父母不能过分替下一代操心，不然会导致他们什么都不会做，完全依赖父母。